/****************************************************************************
* drivers/analog/ltc1867l.c
*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership. The
* ASF licenses this file to you under the Apache License, Version 2.0 (the
* "License"); you may not use this file except in compliance with the
* License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
* WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
* License for the specific language governing permissions and limitations
* under the License.
*
****************************************************************************/
/****************************************************************************
* Included Files
****************************************************************************/
#include <nuttx/config.h>
#include <sys/types.h>
#include <sys/ioctl.h>
#include <stdio.h>
#include <string.h>
#include <stdbool.h>
#include <errno.h>
#include <assert.h>
#include <debug.h>
#include <nuttx/arch.h>
#include <nuttx/kmalloc.h>
#include <nuttx/analog/adc.h>
#include <nuttx/analog/ioctl.h>
#include <nuttx/analog/ltc1867l.h>
#include <nuttx/semaphore.h>
#if defined(CONFIG_ADC_LTC1867L)
/****************************************************************************
* Pre-processor Definitions
****************************************************************************/
/* Device uses SPI Mode 1: CKPOL = 0, CKPHA = 0 */
#define LTC1867L_SPI_MODE (SPIDEV_MODE0)
/****************************************************************************
* Private Types
****************************************************************************/
struct ltc1867l_dev_s
{
FAR const struct adc_callback_s *cb;
FAR struct spi_dev_s *spi;
unsigned int devno;
FAR struct ltc1867l_channel_config_s *channel_config;
int channel_config_count;
sem_t sem;
};
/****************************************************************************
* Private Function Prototypes
****************************************************************************/
static void adc_lock(FAR struct spi_dev_s *spi);
static void adc_unlock(FAR struct spi_dev_s *spi);
/* ADC methods */
static int adc_bind(FAR struct adc_dev_s *dev,
FAR const struct adc_callback_s *callback);
static void adc_reset(FAR struct adc_dev_s *dev);
static int adc_setup(FAR struct adc_dev_s *dev);
static void adc_shutdown(FAR struct adc_dev_s *dev);
static void adc_rxint(FAR struct adc_dev_s *dev, bool enable);
static int adc_ioctl(FAR struct adc_dev_s *dev, int cmd, unsigned long arg);
/****************************************************************************
* Private Data
****************************************************************************/
static const struct adc_ops_s g_adcops =
{
.ao_bind = adc_bind, /* ao_bind */
.ao_reset = adc_reset, /* ao_reset */
.ao_setup = adc_setup, /* ao_setup */
.ao_shutdown = adc_shutdown, /* ao_shutdown */
.ao_rxint = adc_rxint, /* ao_rxint */
.ao_ioctl = adc_ioctl /* ao_read */
};
/****************************************************************************
* Private Functions
****************************************************************************/
/****************************************************************************
* Name: adc_lock
*
* Description:
* Lock and configure the SPI bus.
*
****************************************************************************/
static void adc_lock(FAR struct spi_dev_s *spi)
{
SPI_LOCK(spi, true);
SPI_SETMODE(spi, LTC1867L_SPI_MODE);
SPI_SETBITS(spi, 16);
SPI_HWFEATURES(spi, 0);
SPI_SETFREQUENCY(spi, CONFIG_LTC1867L_FREQUENCY);
}
/****************************************************************************
* Name: adc_unlock
*
* Description:
* Unlock the SPI bus.
*
****************************************************************************/
static void adc_unlock(FAR struct spi_dev_s *spi)
{
SPI_LOCK(spi, false);
}
/****************************************************************************
* Name: adc_bind
*
* Description:
* Bind the upper-half driver callbacks to the lower-half implementation.
* This must be called early in order to receive ADC event notifications.
*
****************************************************************************/
static int adc_bind(FAR struct adc_dev_s *dev,
FAR const struct adc_callback_s *callback)
{
FAR struct ltc1867l_dev_s *priv =
(FAR struct ltc1867l_dev_s *)dev->ad_priv;
priv->cb = callback;
return OK;
}
/****************************************************************************
* Name: adc_reset
*
* Description:
* Reset the ADC device. Called early to initialize the hardware. This
* is called, before ao_setup() and on error conditions.
*
****************************************************************************/
static void adc_reset(FAR struct adc_dev_s *dev)
{
}
/****************************************************************************
* Name: adc_setup
*
* Description:
* Configure the ADC. This method is called the first time that the ADC
* device is opened. This will occur when the port is first opened.
* This setup includes configuring and attaching ADC interrupts. Interrupts
* are all disabled upon return.
*
****************************************************************************/
static int adc_setup(FAR struct adc_dev_s *dev)
{
return OK;
}
/****************************************************************************
* Name: adc_shutdown
*
* Description:
* Disable the ADC. This method is called when the ADC device is closed.
* This method reverses the operation the setup method.
*
****************************************************************************/
static void adc_shutdown(FAR struct adc_dev_s *dev)
{
}
/****************************************************************************
* Name: adc_rxint
*
* Description:
* Call to enable or disable RX interrupts
*
****************************************************************************/
static void adc_rxint(FAR struct adc_dev_s *dev, bool enable)
{
}
/****************************************************************************
* Name: adc_ioctl
*
* Description:
* All ioctl calls will be routed through this method
*
****************************************************************************/
static int adc_ioctl(FAR struct adc_dev_s *dev, int cmd, unsigned long arg)
{
FAR struct ltc1867l_dev_s *priv =
(FAR struct ltc1867l_dev_s *)dev->ad_priv;
FAR struct spi_dev_s *spi = priv->spi;
int i;
uint16_t command;
uint16_t data;
int32_t postdata;
int ret = OK;
if (cmd == ANIOC_TRIGGER)
{
while (nxsem_wait(&priv->sem) < 0);
adc_lock(spi);
for (i = 0; i <= priv->channel_config_count; i++)
{
SPI_SELECT(spi, priv->devno, true);
if (i < priv->channel_config_count)
{
command = priv->channel_config[i].analog_multiplexer_config |
priv->channel_config[i].analog_inputmode;
command = command << 8;
}
else
{
command = 0;
}
data = SPI_SEND(spi, command);
up_udelay(2);
SPI_SELECT(spi, priv->devno, false);
up_udelay(4);
if (i > 0)
{
if (priv->channel_config[i - 1].analog_inputmode ==
LTC1867L_UNIPOLAR ||
(priv->channel_config[i - 1].analog_inputmode ==
LTC1867L_BIPOLAR &&
data >= 0 && data <= 0x7fff))
{
postdata = data;
}
else
{
postdata = -(0xffff - data) - 1;
}
priv->cb->au_receive(dev, priv->channel_config[i - 1].channel,
postdata);
}
}
adc_unlock(spi);
nxsem_post(&priv->sem);
}
else
{
aerr("ERROR: Unrecognized cmd: %d\n", cmd);
ret = -ENOTTY;
}
return ret;
}
/****************************************************************************
* Public Functions
****************************************************************************/
/****************************************************************************
* Name: ltc1867l_register
*
* Description:
* Register the LTC1867L character device as 'devpath'
*
* Input Parameters:
* devpath - The full path to the driver to register. E.g., "/dev/adc0"
* spi - An instance of the SPI interface to use to communicate with
* LTC1867L
* devno - SPI device number
* channel_config - A pointer to an array which holds the configuration
* for each sampled channel.
* channel_config_count - Number of channels to sample
*
* Returned Value:
* Zero (OK) on success; a negated errno value on failure.
*
****************************************************************************/
int ltc1867l_register(FAR const char *devpath, FAR struct spi_dev_s *spi,
unsigned int devno,
FAR struct ltc1867l_channel_config_s *channel_config,
int channel_config_count)
{
FAR struct ltc1867l_dev_s *adcpriv;
FAR struct adc_dev_s *adcdev;
int ret;
/* Sanity check */
DEBUGASSERT(spi != NULL);
DEBUGASSERT(channel_config != NULL);
/* Initialize the LTC1867L device structure */
adcpriv =
(FAR struct ltc1867l_dev_s *)kmm_malloc(sizeof(struct ltc1867l_dev_s));
if (adcpriv == NULL)
{
aerr("ERROR: Failed to allocate ltc1867l_dev_s instance\n");
return -ENOMEM;
}
adcpriv->spi = spi;
adcpriv->devno = devno;
adcpriv->channel_config = channel_config;
adcpriv->channel_config_count = channel_config_count;
ret = nxsem_init(&adcpriv->sem, 1, 1);
if (ret < 0)
{
kmm_free(adcpriv);
return ret;
}
adcdev = (FAR struct adc_dev_s *)kmm_malloc(sizeof(struct adc_dev_s));
if (adcdev == NULL)
{
aerr("ERROR: Failed to allocate adc_dev_s instance\n");
nxsem_destroy(&adcpriv->sem);
kmm_free(adcpriv);
return -ENOMEM;
}
memset(adcdev, 0, sizeof(struct adc_dev_s));
adcdev->ad_ops = &g_adcops;
adcdev->ad_priv = adcpriv;
/* Register the character driver */
ret = adc_register(devpath, adcdev);
if (ret < 0)
{
aerr("ERROR: Failed to register adc driver: %d\n", ret);
kmm_free(adcdev);
nxsem_destroy(&adcpriv->sem);
kmm_free(adcpriv);
}
return ret;
}
#endif